The study, published in Behavioral Sciences and the Law this month, analyzed data from 5,563 face-to-face and household interviews that were part of the National Comorbidity Study Replication, a Harvard-led survey conducted in the early 2000s. The survey assessed respondents’ mental health, including several questions about whether or not they had patterns of impulsive anger, how many guns they owned and whether or not they carried guns outside of the home (respondents who were headed to a target range or who carried a gun as part of their job were excluded).

One of the most significant findings was the three-way association between individuals who owned multiple guns, carried a gun outside of the home and expressed a pattern of angry, impulsive behavior. Study participants who owned six or more guns were found to be four times more likely to carry guns outside of the home and to be in the high-risk anger group than participants who owned one firearm.

Participants who were considered to have a high risk for impulsive anger responded affirmatively to some or all of the following questions: “I have tantrums or angry outbursts;” “Sometimes I get so angry I break or smash things;” and “I lose my temper and get into physical fights.”

Married men under the age of 30 who live in outlying areas around cities were more likely than other demographics to show a pattern of spontaneous anger while simultaneously having access to guns. There were also significant regional differences in gun ownership rates among respondents. Respondents from the Midwest, South and West were much more likely to own a gun than those from the Northeast.

Gun violence is a major problem in the United States. As The Atlantic reported in January, although the United States makes up less than 5 percent of the world’s population, it contains 35 to 50 percent of the world’s civilian-owned guns. According to the Centers for Disease Control and Prevention, in 2013, there were more than 33,000 firearm deaths in the U.S., 11,208 of which were deemed homicides.

The relationship between gun violence and mental health is a divisive issue. “So we have a problem with gun violence,” said Jeffrey Swanson, Ph.D., professor in psychiatry and behavioral sciences at Duke University School of Medicine and lead author of the study. “When do we focus on it? We tend to focus on it when there's a horrifying mass-casualty shooting by a disturbed young man,” he said. “But the thing is, mental illness and gun violence are two very important, very complicated population health problems that come together only on their edges.”

Indeed, while the Behavioral Sciences study showed a relationship between impulsive violence and gun ownership, the study did not find much overlap between having major mental illness -- such as schizophrenia or bipolar disorder -- and being impulsive, anger-prone and having access to firearms. This corroborates previous research indicating that the majority of people who suffer from mental illness are not likely to be violent. (Only about 4 percent of violence can be attributed to major mental illness -- interpersonal violence is usually caused by other factors, such as substance abuse).

What the study did show is an association between individuals who showed signs of a mental disorder and an increased risk for impulsive gun-related violence. These common mental disorders, however, include extremely wide-ranging group of conditions, from depression to post-traumatic stress disorder to substance abuse to eating disorders and more -- conditions that when considered in tandem, affect a substantial portion of the population.

Federal laws mandate that individuals who have been involuntarily committed or legally deemed mentally ill can have their weapons taken away from them, but some states, like New York, have taken gun control legislation a step further. Under New York's 2013 Safe Act, mental health workers are responsible for reporting patients who are “likely to engage in conduct that would result in serious harm to self or others.”

According to the New York Times, the database of individuals considered too mentally unstable to carry a firearm had grown to 34,000 names by the end of last year, creating an environment that mental health advocates fear could stigmatize mental illness and prohibit people from seeking treatment for mental health issues.

Even beyond the possibility of further stigmatizing mental illness, as the Behavioral Sciences study authors wrote in their report, restricting gun access based on common mental disorders that affect a wide swath of the population would be an unpopular and impossible proposition:

Only a small minority of the people with such disorders are subject to current gun restrictions based on mental disorder, as they are never involuntarily hospitalized. Nor would it be easy for authorities otherwise to identify many of them as having one of these common mental disorders, as they will never have sought treatment. Even if these common disorders could be identified, furthermore, gun exclusions that swept up such a large proportion of the general population are not likely to be politically viable.

The study authors argue that a more effective policy measure might be to restrict gun access based on an individual's arrest history. Arrests that could indicate a history of impulsive or angry behavior (for example, criminal records of misdemeanor violence, DWIs and domestic violence restraining orders) would likely serve as a more feasible and less discriminatory indicator of an individual's gun violence risk.

"The group that we focus on goes far beyond regular anger," Swanson told Mother Jones. "The most volatile people are slipping through the cracks."